HIGH-LEVEL EXPRESSION OF A HETEROLOGOUS PROTEIN IN LACTOBACILLUS-PLANTARUM AND ITS EFFECT ON THE PERSISTENCE OF THE RECOMBINANT STRAIN IN SILAGE

This paper reports the high level expression of the Staphylococcus aur eus cat gene in Lactobacillus plantarum using the expression vector pM TL500F. When the recombinant strain of L. plantarum was grown in pure culture, CAT contributed 1.4% of the total soluble cell protein. The r ecombinant strain of L. plantarum continued to express a high level of CAT when inoculated into silage, the heterologous protein constitutin g up to 1.75% of the total soluble cell protein. The recombinant L. pl antarum strain was still able to survive and proliferate when inoculat ed into silage, despite its additional metabolic load.